Screen



C.- R. ALLEN.

' SCREEN.

APPLICATION FILED A". 12. 1920.

1369,51 1. I Patented Feb. 22, 1921.

{NVENTOR amines e ALLEN ATTORNEY I II IIIIIIIIIIIIIIIIIIII UNITED STATES PATENT OFFICE.

CHARLES It. ALLEN, OF OAKLAND, CALIFORNIA.

SCREEN.

T 0 all whom it may concern.-

Be it known that I, CHAnL-Es R. ALLEN, a citizen ofthe United States, residing at Oakland, in the county of Alameda and. State of California, have invented a new and useful Improvement in Screens, of which the following is a specification. A

This invention relates to screens and especially to a screen adapted for handling coarse materials such as crushed rock, coal, etc.

One of the objects of the present invention is to provide a simple substantial efficient screen adapted for handling crushed rock, coal and the like, directly at the mine or quarry, and capable of thoroughly distributing and rapidly screening the whole of the material delivered thereto without resorting to the use of power driven shakers, agitators or the like.

Another object of the invention is to provide a screen which is inclined both longitudinally and laterally, and further to pro vide a novel mounting therefor which will permit the material passing over the screen to impart a rocking movement thereto.

Further objects will hereinafter appear.

The invention consists of the parts and the construction, combination and arrangement of parts as hereinaftermore fully described and claimed, having reference to the accompanying drawings, in which Figure 1 is a perspective view of the screen.

Fig. 2 is a cross section of the same.

Referring to the drawings in detail, A indicates a screen in general, and B a frame or suitable support therefor. The screen proper forms thebottom portion of aframe, consisting of side sections 2, end sections 3, and cross bars 4;. The screen may be constructed of perforated plates or the like, but preferably of bars extending longitudinally of the frame and suitably interspaced for the purpose required. The frame B is in this instance constructed of a pair of sill plates 5, supported by timbers 6 and braces 7 the plates being tied together by cross timbers 8 and braces 9.

By referring to the drawings, it will be seen that the screen is inclined longitudinally and also laterally, and that the material to be screened is delivered thereto by a chute or similar means indicated at 10. This chute deposits the material on the upper lefthand corner of the screen and the material Specification of Letters Patent.

Application filed April 12, 1920. Serial No. 373,025.

will therefore travel both longitudinally and crosswise thereof, while passing over the screen. Again by referring to Fig. 2 it will be seen that a rockingsupport has been provided for the screen, and that the sides are supported by resilient members, to-wit, springs 11. This is of importance as it permits of a rocking movement as the material passes over the screen, due to the constant shifting of the weight. This is important as it materially increases the screening capacity of the screen and the efficiency of the same. The rocking support consists of a shaft 12, supported in bearing members 13, secured on the cross timbers 8. This shaft is connected with the screen frame by bearing members 14, secured to the cross bars 4, and a resilient support for the opposite sides of the screen is formed by placing springs 11 between the ends of the cross bars 4.- and the sill plates 5. The springs serve as a means for normally supporting the screen on a predetermined lateral incline. Delivery of material to the upper portion of the screen and the lefthand side thereof however unbalances the screen or depresses the lefthand side, and as the material slides downwardly over the bars and simultaneously traverses the same, due to the lateral incline, it can readily be seen that the weight'of the material gradually shifts to the opposite side, thereby shifting the center of weight and again rocking the screen. This rocking movement is taking place continu ously during the operation of the screen and rocking movement is thereby transmitted which materially increases the efficiency and capacity of the screen without resorting to the use of power driven shakers, agitators or the like.

While one screen is here shown, it is obvious that a plurality of the same may be placed in alinement if desired; similarly that while certain features of the invention are more or less specifically illustrated, it is obvious that changes may be resorted to within the scope of the appended claims; further that the materials and finish of the several parts employed may be such as the experience and judgment of the manufacturer may dictate or varying conditions may demand.

Having thus described my invention, what I claim and desire to secure by Letters Patent is 1. A device of the character described comprising a frame, a screen forming a bottom for the frame, said screen being disposed in a single plane and longitudinally and laterally inclined, a central rocking support for the frame and a resilient support for each side of the frame.

' 2. A device of the character described com,- prising a screen, which is longitudinally and laterally inclined, a shaft centrally disposed below the screen and extending longitudinally from end to end thereof, bearing members supporting the screen on the shaft to permit rocking movement of'the screen, a'

supporting frame disposed below the screen and supporting the shaft, and a plurality of springs arranged under each side of the screen, said springs being interposed between the supporting frame and the screen to normally maintain the screen on a predetermined lateral incline.

A device of the character described comprising a screen, said screen being disposed in a single plane and inclined longitudinally and laterally, a rocking support extending longitudinally of the screen, and'mean's for limiting the rocking movement of the screen.

In testimony whereof I have hereunto set my hand in the presence of tWo subscribing Witnesses. p 7

CHARLES R. ALLEN.

WVitnesses:

W. W. HEALEY, C. M. 'A'rHER'roN. 

